Top-Level Domains Introduced with the Domain Name System on ARPANET.

On 1 January 1985, several top-level domains introduced with the launch of the Domain Name System (DNS) on the ARPANET network in the United States.

The .com domain was created for commercial organizations.
The .org domain was created for non-profit organizations.
The .net domain was created for network providers and infrastructure.
The .edu domain was created for educational institutions.
The .gov domain was created for United States government agencies.
The .mil domain was created for the United States military.

The early domain registration system was administered by the University of Southern California Information Sciences Institute in Los Angeles.

On 1 January 1985, nordu.net became the first domain name created in the Domain Name System, but it was used for technical infrastructure rather than public registration.

Later, on 15 March 1985, symbolics.com was registered by Symbolics Inc., becoming the first domain name officially registered through the public registration process.
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